TW200813326A - Concrete agitating drum driving device - Google Patents

Abstract

An agitating drum driving device comprises a hydraulic motor (81) for rotating an agitating drum (1), and a swash-plate type hydraulic pump (10) connected to a combustion engine (60) to supply pressurized oil to drive the hydraulic motor (81). When the engine rotation speed is not higher than a predetermined speed, the swash-plate angle of a swash-plate (64) is regulated to keep a differential pressure between a pressure of the pressurized oil and a load pressure acting on the hydraulic motor (81) constant. When the engine rotation speed rises above the predetermined speed, the flow rate of he pressurized oil is increased as the engine rotation speed increases while relatively decreasing an increasing rate of the flow rate of the pressurized oil with respect to an increase rate of the engine rotation speed as the engine rotation speed increases.

Description

200813326 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a type of disturbing drum drive device, a hydraulic millet and a liquid-recognition, and a t-coating for a concrete sandalwood card using a variable night pressure motor. bundle. [Prior Art] A mixing drum that can be used for water, used for falling #. The vehicle is equipped with concrete mixing °; sandalwood and discharge are available from the feeding hopper (7)n water

(4). The agitating drum is driven by a hydraulic motor. A hydraulic circuit for such a concrete mixing drum is proposed by Japanese Patent Publication No.: 724 〇 5A, published by the Japanese Patent Office in the Japanese Patent Office. In this hydraulic drive circuit, the hydraulic motor is supplied with pressurized oil from a variable capacity hydraulic pump. The variable capacity hydraulic pump contains dynamics that change the pumping rate of the pump. The §Hui actuator operates in response to the pump discharge pressure of the variable capacity hydraulic pump. A load sensing valve regulates the pump discharge pressure supplied to the actuator, thereby maintaining a differential pressure between the pump discharge pressure and a load pressure, wherein the hydraulic motor operates at a fixed value under the load pressure . When the differential pressure is maintained at a fixed value, the pressurized oil flow rate supplied from the variable capacity hydraulic pump to the hydraulic motor is also maintained at a fixed value. As a result, even when the rotational speed of the variable displacement hydraulic pump driven by the internal combustion engine is changed, the rotational speed of the agitating drum is maintained at a fixed rotational speed. SUMMARY OF THE INVENTION However, by simply changing the capacity of a variable capacity hydraulic pump, 7 200813326 maintains the discharge flow rate of the hydraulic pump at a fixed range of engine rotational speed from the idling rotational speed region to the high speed rotational region. The value is very difficult. In order to maintain the discharge flow rate of the hydraulic pump, it may be necessary to adjust the output torque of the internal combustion engine 1. For example, in the range from the idling rotational speed region to the low-speed rotation, it may be necessary to increase the fuel i to the internal combustion engine to be used when the internal combustion engine is in a range from the idling rotational speed region to the low-speed rotational region. When operating within the range, the sufficient rotational torque is input into the liquid = 7. However, this engine control increases the fuel consumption of the internal combustion engine. The purpose of the present invention is to reduce the use as a drive for water mixing. : The fuel consumption of the internal combustion engine used by the power source of the concrete mixing drum. To achieve the above object, a concrete agitation device provided by the present invention comprises a hydraulic motor which is connected to the concrete "rolling together" A hydraulic pump is driven by a combustion engine to supply pressurized oil to a hydraulic motor to cause the hydraulic motor to rotate. Two hydraulic actuators are reactive with the driving force of the actuator and a load. The sensing valve, which generates the driving pressure of the actuator by reducing the pressing force of the pressurized oil, is used for the pressure of the pressurized oil and the load: Maintain a differential pressure between the forces, when:: The engine rotation speed is not higher than the predetermined speed, the hydraulic motor: operates at a fixed level under the load pressure. ', in the disturbance drum drive device Contains a mechanical device that increases the flow rate of the pressurized oil as the engine's rotational speed increases as the engine's rotational speed increases, at a predetermined speed, while the engine's rotational speed increases. The increase, while the increase in the rate of rotation of the engine, substantially reduces the rate of increase of the flow rate. The details and other features and advantages of the present invention are set forth in the remainder of the specification and are shown in the accompanying drawings. the way】

Fig. 1A and the circle 1 r, the field ϊ 〇乂 and the Fig. 1β, the concrete mixing drum driving device for the concrete mixing truck which can be used with water contains a pump unit 5〇, a motor unit 8 〇, a reservoir % and hydraulic access to these units and reservoirs. The motor unit 80 includes a hydraulic motor 81 that rotates the concrete mixing drum 1 via the transfer device 2. The hydraulic motor 81 includes two ports 'the first hydraulic passages 51 to which the second hydraulic passages 52 are respectively connected. (4) The motor tether is selectively supplied to the hydraulic pressures of the first hydraulic passage 51 and the second hydraulic passage $ to rotate in the normal direction and the _ reverse direction. The pressure relief valve 82 is connected to the first hydraulic passage 51. The pressure in the first liquid dust passage $ is taken into account by 82 as the pilot dust force for opening the release valve 82. The pressure in the second liquid passage 52 is via the piston unit. 84 and the orifice 86 are input into the pressure relief valve 82, and are used to reduce the pressure of the pressure relief valve 82. The pressure in the (IV) passage $^ is also input to the pressure relief valve 82 via the orifice 88. Among them, as another indexing pressure for closing the pressure relief valve 82. In response to these pilot grindings 9 200813326, the pressure relief valve 82 is in the first hydraulic soil cleaning ^ ^ ^ from & The pressure in i is opened relative to the pressure in the second hydraulic passage 52, which is used to increase the working oil of the first hydraulic passage 51. Released into a filling channel 58, and the 阙82 is closed after a while. The pressure relief valve 82 absorbs the hydraulic motor 8 1 because of the cockroach, the cockroach, the cockroach The pressure in the hydraulic passage 51 changes rapidly and may encounter an impact. The pressure relief valve 8 3 is connected to the first, which is a hydraulic passage U The pressure in the second hydraulic passage 52 is among the rim eight relief valves 83 as the pilot pressure for opening the pressure relief valve 83. In the first you, the pressure in the nighting passage 5 1 The pressure release valve 83 is input through the piston unit 85 and the orifice 4 port 87 as the indexing pressure for closing the pressure reading 83. The fort force in the second hydraulic passage 52 is also via the hole 89 The pressure relief valve 83 is acted upon as another pilot pressure for closing the pressure relief: 83. The pressure in the pressure relief valve 83 in the whistle-, six-two beta...the hydraulic passage 52 is relative to When the pressure in the first 'two-way suppression' rapidly increases, the second liquid helium channel 5 ? > + ^ ^ , , , and the working oil are released to the filling channel: The pressure relief valve 83 is closed after a while. The pressure relief valve 83 thereby absorbs the impact of the motor 81 due to the rapid pressure in the second hydraulic passage 52. The impact is described in the impact 2 The valves 82 and 83 provide a function that is generally known in the absence of a structure. t] The bucket is forced to be 58 via the check valve 55. Connected to the first hydraulic passage 51. The feed through if 52. 8 is also connected to the second hydraulic passage 10 via the check valve 50 200813326 The motor is inside the outer casing of the 80 and the gold and the π and the bedding are stored 90 The two are connected to each other via the outflow force 91. The scratching is in the gentleman mountain type cold part benefit 92 and the oil filter 93 system δ is in the delta sea outflow channel 91. The fruit unit 50 contains one by internal combustion 60 driven hydraulic pump 10, an additional pump i丨, a thousand one-way valve 59, a connection switching valve 20, 4 load sensing valve 40, a shut-off 7 open valve 70 and a high pressure selector Valve 1 6 〇

The first hydraulic passage 51 and the first cranial long circuit 52 are connected to the casing i $ i ^ <,, the suction passage 12 of the hydraulic pump 以及 and the discharge passage 13 via the connection switching valve 20 . In the case of a white haiku, a ^ , ° w forms a closed hydraulic circuit between the hydraulic motor 81 and the hydraulic pump 1 。. The hydraulic pump 10 pressurizes the working oil sucked from the suction passage 12 and discharges the oil into the discharge passage 13. The suction passage 12 is filled with the feed oil supplied by the $u via the check valve 54. The feed pump 11 is rotated in synchronism with the hydraulic pump 1 ,, and the supply passage is supplied via 95 from the working oil from the sump. The working oil in the additive feed Siam 58 has a function of filling the first hydraulic passage 51 via the check valve 55 and filling the second hydraulic passage 52 via the check valve %. The addition passage 58 communicates with the reservoir 9 through the pressure relief valve 59. When the pressure in the material feed 58 rises above a predetermined release pressure, the pressure relief valve 59 returns the excess working oil discharged from the feed pump u to the reservoir 90. The working oil sucked by the additive pump 11 is supplied from the storage 11 200813326 : 9〇 via the passage 95. A sifter 96 is provided in the channel 95. The outline of the chestnut and the outer casing of the motor unit 8 are connected to each other via the outflow passage 97. The hydraulic pump 10 is rotated in synchronization with the internal combustion engine 60. The pump rotation speed of the hydraulic pump is thus equal to the engine rotation speed of the internal combustion engine 60. The suction passage 12, the discharge passage 13, the first hydraulic passage 51, and the second hydraulic passage 52 are connected to the connection conversion switching valve 2''. The connection conversion ^ 20 converts the three sections a_c by the operation performed by the author. In the section ,, the connection switching valve 2 connects the suction passage 12 to the first hydraulic pressure Siam 51, and connects the discharge passage 13 to the second hydraulic passage in the section B, and connects the switching valve 2 to the discharge passage 13 The suction passage 12 is connected to the second hydraulic passage 52 by being connected to the first hydraulic passage 5. In the section c, the connection switching valve 20 disconnects the suction passage 12 and the discharge passage 13 from the first hydraulic passage 51 and the second hydraulic passage 52, respectively. Connecting the switching valve 20 thereby shifts the normal rotation, the reverse rotation, and the stop rotation of the hydraulic motor 8A. A swash plate type piston pump is used as a hydraulic pump. The discharge flow rate of the hydraulic pump 1 is regulated by an actuator 14 that adjusts the hydraulic pump 10 in response to the actuator driving pressure supplied from the load sensing valve 40 and the opening valve 70. Swashplate angle. For this purpose, the actuator 14 and the disconnect valve 70 are connected by an actuator passage 18. The actuator 14 reduces the discharge flow rate of the hydraulic pump j 随着 as the actuation increases the hydraulic pressure in the passage 18. The disconnect valve 70 has two sections A and B. In section a, the break valve 12 200813326 opens the valve 70 to connect the actuator passage 18• to the load sensing valve 4〇. In section b, opening the valve 70 connects the actuator passage 18 to the discharge passage u. The shut-off valve 70 reacts to the indicated pressure input from the discharge passage 13 from the discharge passage 13 to switch the sections. The disconnect valve 70 includes a spring 73 that applies an elastic force to the disconnect valve 7 in the direction for operating the section A. The pilot pressure in the pilot pressure passage 72 pushes the opening valve 70 in the reverse direction of the spring force of the spring 73. The spring force of the spring 73 is set such that when the pilot pressure in the pressureless passage 72 reaches a predetermined pressure substantially in the range of millions of MPa, the valve 7 is disconnected from the zone. Segment A switches to segment B. This occurs when the connection switching valve 2 has been switched to the section c and the discharge passage 13 is thus closed in a state in which the hydraulic pump 1 is in operation. Conversely, when the pilot pressure is less than the predetermined pressure, the valve 7 is opened to maintain the section A. In section A, the disconnect valve 7 is connected to the load sensing port 18 via the orifice. This condition corresponds to a situation in which the disturbing drum 1 is in operation. The field b load sensing valve 40 has two sections A and B. When the disconnect valve 7 is in zone #又于A and the load sensing valve 4 is in zone a, the sequence in the channel 18 is released to the reservoir. The actuator passage 18 is connected to the discharge passage 13 when the opening valve is in the zone & A and the load sensing valve 4 () is in the section 6. The load sensing valve 4G is converted by a differential pressure between the load pressure in the first hydraulic passage 51 or the first pressure passage 52 and the pressure in the discharge passage 13 at 13 200813326. Herein, the load pressure is a pressure acting on the hydraulic motor 81 to rotate the agitating drum 1. The pressure in the discharge passage 13 corresponds to the discharge pressure of the hydraulic pump 10. The differential pressure system is proportional to the flow rate of the discharge passage 13. The load sensing valve 40 adjusts the pressure in the actuator passage 18 by connecting the actuator passage 18 to the discharge passage 13 and the reservoir ' to a preset ratio according to the differential pressure. In other words, the discharge pressure of the hydraulic pump 反 is lowered in response to the differential pressure, and is thus supplied to the actuator passage 18 as the actuator drive pressure. For this purpose, the load sensing valve 4A includes a spring 43 that applies an elastic force to the load sensing valve 40 in the direction for the application section A. The load sensing valve 40 also includes a first indexing channel 4 J. The second guiding channel 42 is used to apply the induced pressure to the load sensing in the same direction as the spring force of the spring 43. The valve 4 is mounted on the load sensing valve 4A in a direction opposite to the resilient force of the spring 43 in the second indicator passage 42. The first pilot passage 41 is connected to the first hydraulic passage 51 and the second hydraulic passage 52 via the high pressure selector valve 16. The high pressure selector valve 16 inputs a higher hydraulic pressure in the first hydraulic passage 51 and the second hydraulic passage 52 into the first pilot passage 41. In other words, the high pressure selection crying valve 16 inputs the load pressure of the hydraulic motor 81 to the first pilot pass = 4 1 . The second pilot channel 42 is connected to the drain channel 丨3. The high pressure selector valve 16 can be constructed, for example, by a shuttle valve. According to the above configuration, when the mixing drum is operated, the actuator 14 is 14 200813326. The swash plate of the hydraulic pump 1 is lowered as the differential pressure between the discharge pressure of the hydraulic pump 10 and the load pressure of the hydraulic motor 81 is increased. The angle, and the swash plate angle of the hydraulic pump 1 增加 is increased as the difference is lowered.

When the agitating drum 1 is to be stopped, the connection switching valve 2 () is switched to the section C to cut off the discharge passage 3 from the hydraulic motor 8. As a result, the discharge pressure of the hydraulic pump 10 is rapidly increased, and accordingly, the disconnect valve 70 is switched from the section A to the section B. In this case, the discharge pressure of the hydraulic pump 1 排放 in the discharge passage 系 is directly supplied to the actuator 14 as the actuator drive pressure is not lowered. Under the influence of such high pressure, the actuator 14 resists the elastic force of the spring 15 to drive the swash plate of the hydraulic pump 1 一个 to a full stroke position, in which the discharge flow rate of the hydraulic pump 1 系 becomes zero. The agitating drum driving device according to the present invention further includes a mechanical device that changes the discharge flow rate characteristic of the hydraulic pump 10 relative to the engine rotational speed: when the rotational speed of the engine is higher than a predetermined speed, the mechanical device follows The increase in the rotational speed of the second embodiment increases the discharge flow rate of the hydraulic pump 10, and at the same time, as the engine rotational speed increases, the rate of increase of the rotational speed of the bow engine is increased. The rate of increase of the predetermined speed system 1 〇 corresponds to the upper speed limit of the money turning speed zone, and is set (4) if it is 600-800 rpm. The mechanical device includes an outflow channel 25 that releases the port acting on the actuator 14 when the actuator 14 travels beyond a predetermined stroke distance in a direction to reduce the rate of release of the hydraulic fruit. P hurts hydraulic pressure. - A hole π 26 is arranged in the outflow channel ^ 15 200813326. = Fig. 2' will now describe the detailed orifice 26 and the fine structure of the outflow channel 25. liquid! The pump 1〇 is of the type of a swash plate, and includes a cylinder 63 and a swash plate 64 enclosed in a space, and the space is formed by the pump casing 62 and the pump cover 61 fixed to the money casing 62. .

The flying body 63 is driven to rotate by the shaft 65. The shaft 65 is subjected to a branch of the cast unit 62 via =72. A top end of the shaft 65 is supported by the pump cover 61 by the bearing 71. The other top of the shaft 65: the toothed pump housing 62 reaches the outside and is connected to the internal combustion engine (9). A plurality of cylinders 66 are arranged in parallel with the central spindle 轴 of the shaft 65 and at a fixed interval along a circular cylinder 63 that surrounds the center. - The living base 68 is inserted into each cylinder %. The pressure chamber π is formed in the cylinder 66 by a tongue base 68. A top end of the piston 68 is projected from the cylinder 66 in the direction of the direction and is slanted by a block (讣(五)). When the vapor red body 63 rotates, each piston 68 is prepared

The swash plate 64 is driven in the axial direction to facilitate reciprocating expansion/contraction of the pressure chamber 67 in a reciprocating manner. X In order to allow the hydraulic pump 1 〇 discharge flow rate to be varied, the swash plate 64 is supported by the pump housing 62 via a trunnion shaft so as to be free to rotate about the center of the trunnion shaft. The spring 15 disposed in the pump housing 62 supports the swash plate 64 in one direction for increasing the swash plate angle of the swash plate. 1 16 200813326 Actuator 1 4 is a recording 4* linear actuator and contains internal fittings? 6 and a column base 75 of the contact with the swash plate 64. The inner tubular member 76 is fixed to the pump cover body 61 in parallel with the central spindle 轴 of the shaft 65. The actuator passage 18 passes through the center of the inner tube % in a direction along the central spindle Ο. The outer slab 7 of the base of the plunger 7 5 is formed on the outer circumference of the inner tube member 76 so that it can be placed in the center of the inner tube 76. Slide freely in the direction. • The pressure in the actuator passage 18 acts on the rear side of the plunger 7 5 from within the outer tubular member 75a. Gentleman Wu, Zhisai 7 ς 果 柱 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 75 Reduce the swashplate angle. The I1 is actuated by the pressure in the actuator passage 18, and the swash angle of the hydraulic pump 10 is reduced. The orifice 26 described above is formed to pass through one wall surface of the outer tube 75a of the plunger 75. In this embodiment a plurality of orifices are formed 26° • External fittings? The outer periphery of the 5a is exposed in the interior of the pump casing 62. Conversely, when the plunger 75 is located in the position shown in the drawing, the inner periphery of the outer tubular member 75a is in contact with the outer periphery of the inner tubular member 76. Therefore, in this case, the orifice 26 is closed. When the plunger 75 is displaced toward the right hand side of the figure such that the orifice 26 can be #, 土,,, Ί M is broken and actuated to actuate the channel 18, the orifice 26 will be in the actuator 诵诘] Part of the working oil in the Yishun Road 18 is released into the space in the pump casing 62 by _ 〃 间. The space system is kept at a low pressure and can therefore be considered a reservoir. The port ° 26 also acts as an outflow channel 25 in this configuration of the hydraulic pump 10. 17 200813326 When the orifice 26 releases a portion of the working oil in the actuator passage 18, the stroke distance of the plunger 75 with respect to the pressure increase in the discharge passage 丨3 becomes significantly smaller. The orifice 26 and the outflow passage 25 thus constitute a mechanical means for varying the discharge flow rate characteristic of the hydraulic pump 10 with respect to the rotational speed of the engine. It should be noted that the orifice 26 reduces the rate of increase of the hydraulic pump 1 〇 discharge flow rate, while allowing the plunger 75 to protrude to the full stroke position based on the hydraulic pressure in the actuator passage 18. As described above, when the operation of the agitating drum 1 is stopped, it is necessary to make the swash plate angle zero, so that the discharge flow rate of the hydraulic pump 1 会 becomes zero. In order to stop the rotation of the agitating drum 1, the connection switching valve 2 is switched to the section C, and the synthesis of the discharge pressure of the hydraulic pump 10 is rapidly increased to cause the column base to move to the full stroke position, in which position The slant angle angle system becomes zero. The size and number of the apertures 26 can thus be determined so that this full stroke of the plunger 75 can be prevented. When the agitating drum 1 is operated, the internal combustion engine 60 drives the hydraulic pump to rotate. The hydraulic pump 10 thus draws the low pressure working oil in the suction passage 12 and discharges the pressurized working oil into the discharge passage. By switching the connection switching valve 20 to any one of the section A and the section B, one of the first hydraulic passage 51 and the second hydraulic passage 52 is supplied with pressurized working oil, and the low pressure The working oil is again circulated from the other of the first hydraulic passage 51 and the second hydraulic passage 52 to the suction passage 12. By circulating the working oil between the hydraulic pump 1A and the hydraulic motor 81 in this manner, the hydraulic motor 81 is rotated, 18 200813326 and the rotation is transmitted to the agitating drum i via the transmission 2. The load sensing valve 40 is supplied with the actuator driving pressure supplied to the actuator ,4 such that the discharge pressure of the hydraulic pump 1〇 in the discharge passage 13 and the hydraulic motor 81 appear in the first hydraulic passage 51 or the first The differential pressure between the load pressures in the two hydraulic passages 52 can be maintained at a predetermined pressure. . When the internal combustion engine 60 is idling, or when the internal combustion engine is operating in the low speed rotation region, the hydraulic pump 10 increases the swash plate angle to compensate for the low speed rotation. % The actuator 14 in the stalking behavior operates within a range of travel distances, while the orifice 26 is closed in this range. The actuator 14 adjusts the swash plate angle of the hydraulic pump 10 such that the differential pressure between the discharge pressure of the hydraulic pump 1〇 and the load pressure of the hydraulic motor 81 can be maintained at a fixed value, or in other words, the hydraulic pump The 1 〇 discharge flow rate can be maintained at a fixed flow rate. Referring to Fig. 3, when the internal combustion engine 6 is idling, or when the internal combustion engine is operating in the low speed rotation region, the actuator 14 reduces the hydraulic pump 10 as the internal combustion engine 6 〇 rotation speed or the rotational speed of the hydraulic pump 10 increases. Swashplate angle. As a result, the flow rate of the pressurized oil supplied from the hydraulic pump 10 to the hydraulic motor 81, or in other words, the rotational speed of the agitating drum 保持 remains fixed. Further, the rotational speed level of the agitating drum 1 in this state is lower than the rated rotational speed of the agitating drum 1. When the rotational speed of the internal combustion engine 60 is further increased, the actuator 14 is coupled to the stroke distance of the column base 75, and the orifices 26 are finally in communication with the space in the pump casing 62. The orifice 26 releases a portion of the hydraulic pump 1 2008 200813326 under a predetermined flow resistance into the space in the pump housing 62. Therefore, in the case where the orifice 26 1 is closed, the decrease in the swash plate angle is more gentle with respect to the increase in the discharge flow rate of the hydraulic pump 10. As a result, in the medium-speed and high-speed rotation regions of the internal combustion engine 60, the rotational speed of the agitating drum 逐渐 gradually increases as the engine rotational speed increases: as shown in Fig. 2 . The rotational speed of the agitating drum 1 reaches the rated rotational speed in this manner. φ Here, the orifice 26 is not formed in the outer tube member 75a, but instead it is possible to provide a stop preventing the swash plate 64 from reducing the swash plate angle to a predetermined angle, thereby transferring the rotation of the agitating roller. The speed increases as the engine's rotational speed increases. However, if the swash plate angle is blocked, the discharge flow rate of the hydraulic pump 10 increases in proportion to the rotational speed of the engine, and the rotational speed of the agitating drum 倾向于 tends to be too fast. Further, when the connection switching valve 20 is switched to the section C, the stopper prevents the actuator 14 from moving the swash plate to a zero position corresponding to the full stroke position of the plunger 75, _ to facilitate the hydraulic pump 1 The discharge flow rate can be made zero. The function of the orifice 26 is to satisfy the following conditions: the increase in the discharge rate of the hydraulic pump 1 变得 becomes more moderate as the rotational speed of the engine increases in the medium-speed and high-speed rotational speed regions, and does not become hydraulic The discharge pressure of the pump is applied to the actuation 14 as a result of switching the connection switching valve to section C, preventing the plunger 75 from driving the swash plate 64 to the zero position. The increase in the discharge flow rate of the hydraulic pump 10 becomes more gradual as the engine rotational speed increases. As the rotational speed of the engine increases, the rate of increase of the hydraulic pump 1 〇 discharge flow rate decreases relative to the engine rotation speed. 20 200813326 The rate of increase is decreasing. In the case of the second embodiment, the orifice 26 is formed in the outer tube, and the outer side is directly connected to the actuating actuator 18 and the storage:: ' and thus the orifice 26 is substantially acted upon as Flow out of channel 25. The operating characteristics of the hydraulic pump can be set in a preferred manner without increasing the number of parts of the agitator drum drive.

The agitating drum driving device described above is to maintain the hydraulic & 〇 discharge flow: at a fixed low level when the internal combustion engine 6 〇 is empty: or 疋 is in the low-speed rotation region, and when the internal combustion engine 6 〇 In the mid-speed or high-I suspected area, the operation of Hiroshi Chong, Chen Yushou, increases the discharge flow rate of the hydraulic pump 10 to a range corresponding to (4) the rotational speed of the roll. Therefore, the fuel consumption of the internal combustion engine 60 can be reduced without affecting the operation of the agitating drum 1 in accordance with the selection of the rolling drive. Patent No. 2, 6-1, 547, 174, filed on Jun. Although the invention has been described above with reference to an example of the invention, the invention is not limited to the examples described above. Modifications and variations of the examples described above will occur to those skilled in the art. For example, it is not necessary to form a plurality of apertures 26 in the outer tubular member 75a. It is also possible to form only one aperture 26 in the outer tubular member 75a as long as the conditions described above can be met. The internal combustion engine 60 can be replaced with any type of combustion engine. An example of the invention in which the proprietary or basic rights are claimed is set forth in the following section. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A and FIG. 1B are hydraulic circuit diagrams of a concrete spoiler according to the present invention; a concrete agitating drum drive; FIG. 2 is a longitudinal sectional view of the hydraulic pump, and the device is provided with the hydraulic pump, and

Fig. 3 is a graph showing the rotation speed of a concrete agitating drum against the engine according to the present invention. Speed characteristic

[Main component symbol description] 1 Concrete mixing drum 2 Transmission unit 10 Hydraulic pump 11 Adding pump 12 Suction channel 13 Discharge channel 14 Actuator 15 Spring 16 High pressure selector valve 17 Port 18 Actuator channel 20 Connection switching valve 25 Outflow channel 26 orifice 40 load sensing valve 22 200813326

41 first indication channel 42 second introduction channel 43 spring 50 pump unit 51 first hydraulic channel 52 second hydraulic channel 54 check valve 55 check valve 56 check valve 58 feed channel 59 pressure relief valve 60 internal combustion engine 61 Pump cover 62 Fruit housing 63 Cylinder block 64 Swash plate 65 Shaft 66 Cylinder 67 Pressure chamber 68 Piston 70 Disconnect valve 71 Bearing 72 Pilot pressure passage 73 Spring 23 200813326 Pillar external fitting Internal fitting Motor unit Hydraulic motor release Pressure valve pressure relief valve piston unit piston unit orifice orifice orifice orifice reservoir outflow channel oil cooler oil filter channel filter outflow channel section section section central spindle 24

Claims (1)

200813326 X. Patent application scope: 1 · A concrete mixing drum driving device, which comprises: a hydraulic motor 'connected to a concrete mixing drum · a hydraulic pump driven by a fuel engine and borrowed Supplying the twisted oil to the hydraulic motor to cause the hydraulic motor to rotate; two kilograms of a hydraulic actuator that reacts to an actuator drive pressure to adjust a flow rate of the pressurized oil; a sense of load The valve is configured to generate an actuator driving pressure by reducing the pressure of the pressurized oil to maintain a differential pressure between the pressure of the pressurized oil and a load pressure 2, and under the load pressure, When the engine rotational speed of the combustion engine is not higher than a predetermined speed, the = pressure motor operates at a fixed level; and a mechanical device when the engine rotation speed is not higher than a predetermined = degree At the time, the mechanical device increases the flow # of the oil with the increase of the rotational speed of the engine, and rotates with respect to the engine as the rotational speed of the engine increases. A rate of increase of the rate of increase of the flow rate is relatively reduced. #2· The concrete mixing drum drive = set according to the scope of the patent, wherein the hydraulic actuator is a linear actuator, and the mechanical garment contains a passage when the actuator stroke exceeds One channel, the channel releases a portion of the actuator drive pressure. 3: A concrete mixing drum drive as claimed in claim 2, wherein the passage comprises an orifice. :····································································· Mounting is free to slide in an outer axial direction of the inner tubular member, the internal force is a plunger in the interior of the outer tubular member and the orifice includes a connection to the outer bore to facilitate passage of the outer tubular member and distance The relative displacement, which will release the driving pressure of the device to the external pipe fittings. 5. The concrete (four) drum driving device described in the fourth paragraph of the patent scope, wherein the Yanhai hydraulic pump is a swash plate type pump, The flow rate of the pressurized oil is changed according to the angle of the swash plate of the swash plate, and the hydraulic pump includes a magazine, and the spring is supported by the slanting plate to increase the angle of the swash plate. The disc 'and the ember plugs in the swashplate in a direction that resists the tampering of the swashplate. 〃 The actuator plunger has an outer portion of the inner tube inner tubular member to which a tubular member is applied on the upper tubular member. The drive pressure is in the interior of an outer tubular member such that an actuator can be actuated to press a propulsive force and a portion of the inner and outer bore members exceed a predetermined one. The concrete sandalwood drum drive of the invention of claim 4, wherein the swash plate type pump comprises a pump housing, and the orifice is configured to be spatially open to the pump housing. 7. The concrete mixing drum driving device according to claim 2, further comprising a connection switching valve including a first section and a second section, and a disconnecting valve, the first zone The section is for selecting a direction of the pressurized oil between the hydraulic pump and the hydraulic motor, and the second section cuts off the supply of the hydraulic oil to the hydraulic motor, and when When the connection switching valve is located in the second section, 詨26 200813326 disconnects the valve to supply pressurized oil, which does not decrease with the actuator driving pressure to the hydraulic actuator. 8. The concrete mixing drum driving device of claim 7, wherein the orifice is formed in a size such that the actuator can be supplied to the hydraulic actuator when the pressure of the pressurized oil is supplied. When the flow rate of the pressurized oil is reduced to zero, and the combined σ is not Ik, the dynamic driving pressure is lowered. L such as π, please patent the first device, wherein, when the engine rotates, the flow rate of the pressurized oil driven by the mixing drum is again "at the predetermined speed, the rated flow of one - the flow rate" The pressure oil corresponds to the mixing drum eleven, round: as the next page. 27